Installation¶
Install with pip¶
Note that to use astrowidgets
with Jupyter Lab you need to
install nodejs from here:
pip install astrowidgets
#
# ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓
# INSTALL NODEJS FROM https://nodejs.org/en/download/
# ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑
#
# (the nodejs on PyPI is *NOT* the right thing)
#
jupyter labextension install @jupyter-widgets/jupyterlab-manager
Install with conda¶
conda installation:
conda install -c conda-forge astrowidgets nodejs
jupyter labextension install @jupyter-widgets/jupyterlab-manager
# Optional, but avoids a rebuild when you open lab
jupyter labextension build
Note
If you are using a virtual environment and
are experiencing problems with the installation, be sure to check and use
the suitable pip
version. Also, if you are having problem even with the following
dependencies installed, please make sure you have the most up-to-date versions.
Upgrade dependencies when and where necessary.
The following dependencies are needed in the kernel of execution
to use astrowidgets
in either Jupyter Lab or Notebook. They should be installed
automatically when you install astrowidgets:
python>=3.6
numpy
astropy
ipywidgets>=7.5
ipyevents>=0.6.3
ginga>=2.7.1
pillow
freetype
aggdraw
jupyterlab>=1
nodejs
opencv
(optional, not installed by default)
After installing dependencies, for Jupyter Lab, run:
jupyter labextension install @jupyter-widgets/jupyterlab-manager
For those using conda
, dependencies from the conda-forge
channel
should be sufficient unless stated otherwise.
Using OpenCV¶
If you wish to use OpenCV to handle the drawing in Ginga, you have two options:
Install OpenCV with pip¶
If you are using pip it looks like the best option is to use the
opencv-python
package, which provides pre-built binaries of most of OpenCV:
pip install opencv-python
However, the opencv-python project is quite clear about being “unofficial” so you should probably read about the project before using.
Install OpenCV with conda¶
This should work on conda:
conda install -c conda-forge opencv
If, after installing opencv
, you get a warning like this:
astrowidgets/core.py:72: UserWarning: install opencv or set use_opencv=False
warnings.warn('install opencv or set use_opencv=False')
then you should try installing a newer version of freetype
:
conda install 'freetype\>=2.10'
For more details, see this discussion of opencv and astrowidgets.
Widget with Ginga toolkit¶
Note
For vectorized drawing in aggdraw
, you can clone
https://github.com/ejeschke/aggdraw/ and install its vectorized-drawing
branch from source.
Notes for Windows users¶
aggdraw¶
It is a known issue that FREETYPE_ROOT
is not set properly if you do
conda install aggdraw
on Windows
(https://github.com/conda-forge/freetype-feedstock/issues/12), which results
in aggdraw cannot load font (no text renderer)
error message when
using the widget with Ginga toolkit. The solution is to update to aggdraw
1.3.5 or later; e.g., conda install aggdraw=1.3.5
.
nodejs¶
In Windows 7, conda install -c conda-forge nodejs
might throw an
IOError
. The workaround for this is to install yarn
and nodejs
outside of conda
from https://yarnpkg.com (the stable version) and
https://nodejs.org (the LTS version), respectively.